y2038: ipc: remove __kernel_time_t reference from headers

There are two structures based on time_t that conflict between libc and
kernel: timeval and timespec. Both are now renamed to __kernel_old_timeval
and __kernel_old_timespec.

For time_t, the old typedef is still __kernel_time_t. There is nothing
wrong with that name, but it would be nice to not use that going forward
as this type is used almost only in deprecated interfaces because of
the y2038 overflow.

In the IPC headers (msgbuf.h, sembuf.h, shmbuf.h), __kernel_time_t is only
used for the 64-bit variants, which are not deprecated.

Change these to a plain 'long', which is the same type as __kernel_time_t
on all 64-bit architectures anyway, to reduce the number of users of the
old type.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

3 files changed, 15 insertions, 16 deletions

diff --git a/include/uapi/asm-generic/msgbuf.h b/include/uapi/asm-generic/msgbuf.h
index 9fe4881557cb..af95aa89012e 100644
--- a/include/uapi/asm-generic/msgbuf.h
+++ b/include/uapi/asm-generic/msgbuf.h
@@ -13,9 +13,9 @@
  * everyone just ended up making identical copies without specific
  * optimizations, so we may just as well all use the same one.
  *
- * 64 bit architectures typically define a 64 bit __kernel_time_t,
- * so they do not need the first three padding words.
- * On big-endian systems, the padding is in the wrong place.
+ * 64 bit architectures use a 64-bit long time field here, while
+ * 32 bit architectures have a pair of unsigned long values.
+ * On big-endian systems, the lower half is in the wrong place.
  *
  * Pad space is left for:
  * - 2 miscellaneous 32-bit values
@@ -24,9 +24,9 @@
 struct msqid64_ds {
 	struct ipc64_perm msg_perm;
 #if __BITS_PER_LONG == 64
-	__kernel_time_t msg_stime;	/* last msgsnd time */
-	__kernel_time_t msg_rtime;	/* last msgrcv time */
-	__kernel_time_t msg_ctime;	/* last change time */
+	long		 msg_stime;	/* last msgsnd time */
+	long		 msg_rtime;	/* last msgrcv time */
+	long		 msg_ctime;	/* last change time */
 #else
 	unsigned long	msg_stime;	/* last msgsnd time */
 	unsigned long	msg_stime_high;
diff --git a/include/uapi/asm-generic/sembuf.h b/include/uapi/asm-generic/sembuf.h
index 0bae010f1b64..137606018c6a 100644
--- a/include/uapi/asm-generic/sembuf.h
+++ b/include/uapi/asm-generic/sembuf.h
@@ -13,9 +13,8 @@
  * everyone just ended up making identical copies without specific
  * optimizations, so we may just as well all use the same one.
  *
- * 64 bit architectures use a 64-bit __kernel_time_t here, while
+ * 64 bit architectures use a 64-bit long time field here, while
  * 32 bit architectures have a pair of unsigned long values.
- * so they do not need the first two padding words.
  *
  * On big-endian systems, the padding is in the wrong place for
  * historic reasons, so user space has to reconstruct a time_t
@@ -29,8 +28,8 @@
 struct semid64_ds {
 	struct ipc64_perm sem_perm;	/* permissions .. see ipc.h */
 #if __BITS_PER_LONG == 64
-	__kernel_time_t	sem_otime;	/* last semop time */
-	__kernel_time_t	sem_ctime;	/* last change time */
+	long		sem_otime;	/* last semop time */
+	long		sem_ctime;	/* last change time */
 #else
 	unsigned long	sem_otime;	/* last semop time */
 	unsigned long	sem_otime_high;
diff --git a/include/uapi/asm-generic/shmbuf.h b/include/uapi/asm-generic/shmbuf.h
index e504422fc501..2bab955e0fed 100644
--- a/include/uapi/asm-generic/shmbuf.h
+++ b/include/uapi/asm-generic/shmbuf.h
@@ -13,9 +13,9 @@
  * everyone just ended up making identical copies without specific
  * optimizations, so we may just as well all use the same one.
  *
- * 64 bit architectures typically define a 64 bit __kernel_time_t,
- * so they do not need the first two padding words.
- * On big-endian systems, the padding is in the wrong place.
+ * 64 bit architectures use a 64-bit long time field here, while
+ * 32 bit architectures have a pair of unsigned long values.
+ * On big-endian systems, the lower half is in the wrong place.
  *
  *
  * Pad space is left for:
@@ -26,9 +26,9 @@ struct shmid64_ds {
 	struct ipc64_perm	shm_perm;	/* operation perms */
 	size_t			shm_segsz;	/* size of segment (bytes) */
 #if __BITS_PER_LONG == 64
-	__kernel_time_t		shm_atime;	/* last attach time */
-	__kernel_time_t		shm_dtime;	/* last detach time */
-	__kernel_time_t		shm_ctime;	/* last change time */
+	long			shm_atime;	/* last attach time */
+	long			shm_dtime;	/* last detach time */
+	long			shm_ctime;	/* last change time */
 #else
 	unsigned long		shm_atime;	/* last attach time */
 	unsigned long		shm_atime_high;